Hybrid Senior Backend Engineer, Models

at hyperexponential

• Job title: Senior Backend Engineer, Models
• Job type: Full Time
• Experience level: Senior
• Salary: PLN 27,000 - PLN 37,000 per month
• Degree requirement: Bachelor's Degree
• Tech skills: AWS, Cloud, EC2, Kotlin, Python, Rust
• Location requirements: Hybrid, Warsaw, Poland

About the role

• Senior Backend Engineer enhancing a scalable AI-powered platform on the Models team. Collaborating and delivering backend solutions with Python, Rust, and Kotlin.

Responsibilities

• Designing and implementing scalable backend solutions that enable the Models platform to handle increasingly complex and nested customer data, directly improving reliability and performance.
• Addressing technical debt and driving forward-looking architectural changes to support rapid growth and evolving customer needs.
• Building reusable components and abstractions that accelerate delivery across the group and empower other teams to move faster.
• Collaborating with cross-functional teams, including those working in Python, Rust and Kotlin, to deliver features that have measurable impact on customer experience and platform adoption.
• Leading by example in ownership, kindness, and proactive problem-solving, fostering a culture of continuous learning and high performance.
• Contributing to the rearchitecture of our core model code base, aligning with modern industry standards and preparing the platform for future challenges.

Requirements

• Architected and delivered complex backend systems with proven experience leading technical initiatives in Python
• Our teams use a combination of Python, Rust and Kotlin. Expect to be upskilled in Rust if you didn't already use it!
• Built and deployed cloud applications at scale, demonstrating the ability to deliver robust solutions in production environments.
• We use AWS with ECS, EC2, Fargate, Lambda
• Designed and managed complex, arbitrary nested data structures tailored to diverse customer requirements.
• Demonstrated strong working knowledge of fundamental computer science and software engineering principles, including algorithms, data structures, complexity, design patterns, and architecture.
• Owned and delivered projects through the complete product development lifecycle, from conception to delivery.
• Collaborated effectively across teams, driving initiatives that improved scalability, reliability, or delivery speed.

Benefits

• Share Options at a highly successful Series B company
• 25 days of non-working + 14 Polish bank holidays
• £5,000 budget for Learning & Development
• Mental Health Support and Therapy via Spectrum Life
• Optional for you: access to Healthcare package provided by Luxmed + Multisport (fully funded by yourself as B2B Contractor)
• Top-spec laptop (MacOS or Windows)
• 26 days of holiday + 14 Polish bank holidays
• Company pension
• 10 days company sick pay at 100% salary, thereafter in line with labour law
• Monthly wellbeing allowance via Juno
• Healthcare package provided by Luxmed
• Multisport card at Classic level
• Top-spec work equipment (MacOS / Windows + additional monitors, mechanical keyboards etc)